1. Field of the Invention
This invention relates to improvements in a relay adapter socket for connecting together small-size multicontact plugs each having a plurality of pin-type contacts.
2. Description of the Prior Art
FIG. 1 shows a three-contact relay adapter socket S for connecting together small-size multicontact plugs P, each of which comprises a cylindrical metal ground terminal 10, an insulating contact holder 11 surrounded by the ground terminal 10 and three pin-type contacts 12 accommodated in the contact holder 11 and serves as a three-contact plug section 1. FIG. 2 shows the detailed construction of the relay adapter socket S. As is shown, the relay adapter socket S comprises a pair of jack sections 3 symmetrically provided in front (i.e., left end in FIG. 2) and rear portions of a cylindrical body 2 and each including a cylindrical ground terminal 30 consisting of metal sheets, an insulating contact holder 31 surrounded by the ground terminal 30 and a plurality of female contacts 33 insertedly held in corresponding female contact accommodation bores 32 of the contact holder 31, the female contacts 33 of each of the jack sections 3 being connected to corresponding female contacts 33 of the other.
The pair of jack sections 3 which are provided in the front and rear portions of the body 2 of the adapter socket S have the same shape for they accommodate the plug sections 1 of the same three-contact small-size multicontact plugs P. However, either jack section 3 is adapted such that it is connected to the plug section 1 of the small-size multicontact plug P on the right side in FIG. 1, i.e., in the second order of relay. Therefore, these jack sections 3 are mounted symmetrically as shown in FIG. 3.
In other words, the jack sections 3 are provided such that the same arrangement pattern of female contacts 33 as before appears when the body 2 is turned 180 degrees about a phantom line w shown in FIG. 2.
Therefore, in the right or rear jack section 3 in FIG. 3 the left side female contact 33-L corresponding to the left side contact pin 12-L of the plug section 1 of the small-size multicontact plug P is found on the left side in plan view, whereas in the left or front jack section 3 like female contact is found on the right side in plan view.
For this reason, when connecting the female contacts 33 of the front and rear jack sections 3 in the body 2 by soldering 35, leads 34 of the central female contacts 33 in the pair jack sections 3 are connected straight, but leads 34 of the left and right side female contacts 33 are connected in a crossed fashion, so that the same contact arrangement pattern as before can be obtained when the front and rear jack sections 3 are turned by 180 degrees. After completion of this connection, the jack sections 3 are assembled in the body 2. Therefore, the assembly is rather cumbersome.